1. Field of the Invention
The present invention relates generally to the field of devices and systems for containing environmentally hazardous buoyant fluids spilled on water such as oil. More specifically the present invention relates to a flow slowing boom including a ramped or horizontal skirt structure for placement at the surface of a body of moving water across the direction of flow for slowing the speed of buoyant fluids in the water to permit the fluids to buoy toward the water surface for containment. The flow slowing boom preferably includes a support structure for deployment at the water surface and connected to a boom anchoring structure for maintaining the position of the support structure, and a skirt structure pivotably suspended from the support structure with pivot means so that water movement pivots the skirt structure out of a suspended vertical orientation to an average position of any of a range of angles beyond vertical at any of a range of angles between 30 degrees and 95 degrees from vertical in the direction of water flow, and preferably at an angle from vertical between 75 and 92 degrees in the direction of water flow, thereby constraining buoyant fluid to flow across the skirt structure thereby slowing the speed of the floating fluid and thus permitting the fluid to buoy to the water surface and become containable by at least one subsequent containment boom. The support structure preferably includes a floatation means, so that the pivot means extends below the floatation means to the skirt structure. The flow slowing boom preferably includes orienting anchor means the skirt structure lower end to orient the skirt structure at a desired angle relative to horizontal suitable for a particular water movement speed.
A boom system is further provided including the flow slowing boom for positioning across the direction of water flow and a downstream series or cascade of conventional containment booms also positioned across the direction of water flow.
A method is also provided of containing fluid floating on a body of moving water including the steps of providing a flow slowing boom having a support structure and a skirt structure pivotally suspended from the support structure, positioning the support structure along the surface of the body of water across the direction of water flow so that the skirt structure extends downwardly from the support structure, providing a boom anchoring structure; securing the support structure in position with the anchoring structure; permitting water movement to pivot the skirt structure to a position angled away from vertical as specified above, and providing at least one containment boom including a downwardly extending skirt portion, positioning the at least one containment boom across the direction of water flow and downstream of the flow slowing boom, such that fluid floating on the surface of the flowing water is slowed by the flow slowing boom, buoys closer to the water surface and at least a portion of the floating fluid is stopped and contained by the containment boom.
2. Description of the Prior Art
There have long been booms having vertical containment skirts and buoyant elements for placement in bodies of water to contain floating fluids capable of causing environmental damage, such as oil. These prior booms have always not been successful in containing floating fluids on moving water, and especially where the movement is rapid.
One prior boom is that of Dreyer, U.S. Pat. No. 6,743,367, issued on Jun. 1, 2004. Dreyer discloses a boom having a boom curtain with expandable pleated panels and the method of boom use. The boom includes a support system, an upper portion for connection to the support system and a main portion having several pleats for increasing the surface area of the boom. Other related prior art references include U.S. Pat. No. 4,738,563 issued to Clark in April of 1988; and U.S. Pat. No. 6,778,469 issued in August of 2004 to McDonald, and U.S. Patent Application 2004/0156266 filed in August of 2004 by McDonald.
It is thus an object of the present invention to provide a flow slowing boom for use in rapidly moving water which includes a skirt structure angled at an average position away from vertical to define a ramp so that fluid floating on the water is slowed as it passes along the skirt structure and thus rises toward the surface with buoyant force to become more readily contained by downstream conventional containment booms, and which can be caused to remain vertical when desired. The invention uses the power of nature by harnessing the energy of the water flow to pivot skirt on the pivot means to orient the skirt.
It is another object of the present invention to provide such a flow slowing boom in which the skirt structure can be oriented at a selected angle relative to vertical through the securing of ballast or anchoring means to the skirt structure.
It is still another object of the present invention to provide a boom system including the flow slowing boom and at least one containment boom and which is suitable for use in a variety of sea conditions with any of a wide range of water current speeds.
It is finally an object of the present invention to provide a method of deploying such a boom system which requires minimal effort, man hours and skill.